Influence of secondary gas on control characteristics of ICP-RF plasma torches

TL;DR

This study uses numerical simulations to analyze how mixing helium as a sheath gas influences the control and behavior of an atmospheric pressure RF plasma torch, focusing on flow, temperature, turbulence, and electromagnetic fields.

Contribution

It introduces a comprehensive numerical model combining MHD, turbulence, and electromagnetic equations to evaluate the effect of helium sheath gas on plasma torch control characteristics.

Findings

Helium addition affects flow and temperature profiles.

Turbulence characteristics are altered by sheath gas composition.

Electromagnetic field distributions are influenced by gas mixing.

Abstract

Thermal plasma characteristics inside an atmospheric pressure Radio-Frequency Argon plasma torch have been studied by numerically solving axis-symmetric 2-D Magnetohydrodynamics equations, energy transport equations and species conservation equation coupled with 2D Maxwell equations in the vector potential form. A renormalization group k - epsilon model was employed to study the turbulence within the torch. Helium is mixed with Argon for injection as the sheath gas, and its effect on the control characteristics of the torch has been studied. A control volume approach and semi-implicit pressure linked equations revised (SIMPLER) algorithm was used to solve the above set of equations to obtain the flow, temperature, turbulence and EM source fields within the torch. Finally, a comparison of the results obtained in our present calculation has been made with other works of similar nature. The torch geometry, flow rates and power dissipation values used in the present calculation are similar to the standard ones available in literature.